The proposed research will continue a systematic investigation into the role of metabolic compartmentation in the regulation of biochemical differentiation in the cellular slime mold, Dictyostelium discoideum. Current efforts will be concerned with defining those regulatory mechanisms which control the rate of synthesis of a major developmental product in this system (i.e., the disaccharide trehalose) and its subsequent compartmentation at the cellular, organelle and microenvironmental levels. The specific aims to be achieved will be: (1) to continue studies on the stabilization of T6P synthase to electrophoresis and isoelectric focusing; (2) to evaluate the following methods for the resolution of the two T6P synthase isozymes: (a) isoelectric focusing, (b) electrophoresis, (c) affinity chromatography and (d) hydrophobic interaction chromatography; (39 to finalize the methodology for production of homogeneous trehalase from vegetative amoebae and characterize the purified glycoprotein; (4) to examine the developmental profile for the isozymes of trehalase and T6P synthase; (5) to develop methods employing Percoll density gradient centrifugation that allows efficient resolution of the major cell types during development for subsequent analysis of cell-type specificity relative to isozyme distribution.